In the beggining of the universe, a gravitational effect like this, would make the concetration of matter higher at the center of the tiny universe "globe", while antimatter would mainly concetrate far from it. Therefore there would be 3 types of reactions :

Since more matter than antimatter would be at the center (hotter area), the matter mass would disappear at higher rates than the antimatter mass and we would therefore have more antimatter than matter as a total. As matter kept decaying at higher rates into energy due to its gravitational effect, the "repel forces" of the antimatter gravity were becoming more dominant, pushing the universe to expand.

And so, the current situation would be:

1) Antimatter is more than matter.
2) Matter continous to decay into energy due to its gravitational effect, and therefore antimatter keeps becoming increasingly dominant
3) We can't detect the antimatter because of its gravitational effect that makes it spread through the entire universe in the form of single individual particles
4) Dark Energy probably is the gravitational effect of this antimatter

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A photon is it's own antiparticle. So if gravity is repulsive for antimatter, there should be no effect on photons. But photons are bent by gravity - this was first shown in 1919.

I didn't say gravity is repulsive for antimatter. I said the antimatter gravity could be repulsive. I'll give some examples of what I mean:

- An antihydrogen atom created on earth would fall downwards practically with the same g as ordinary matter, because the attractive gravitational effect of earth is considerably higher than the repulsive effect it would create.
- A hydrogen atom and and an antihydrogen atom would neither attract nor repel, as their gravitational "forces" would cancel each other.
- 2 antihydrogen atoms would repel each other
- 2 hydrogen atoms would attract 1 antihydrogen atom with a force twice as great as the antihydrogen atom would repel them

- An antihydrogen atom created on earth would fall downwards practically with the same g as ordinary matter, because the attractive gravitational effect of earth is considerably higher than the repulsive effect it would create.
- A hydrogen atom and and an antihydrogen atom would neither attract nor repel, as their gravitational "forces" would cancel each other.
- 2 antihydrogen atoms would repel each other
- 2 hydrogen atoms would attract 1 antihydrogen atom with a force twice as great as the antihydrogen atom would repel them

I guess you made all this up. There is nothing in current physics theory to justify any of it.

I guess you made all this up. There is nothing in current physics theory to justify any of it.

I know there isn't. If you look at the topics title, I did post this "hypothetically" and my question was if there is any experimental data that rules it out, because I looked for it and failed to find any.